blueprint tutorial

battery_low_mobile_notification.yaml

blueprint:
  name: Low battery level detection & notification for all battery sensors
  description: Regularly test all sensors with 'battery' device-class for crossing
    a certain battery level threshold and if so execute an action.
  domain: automation
  input:
    threshold:
      name: Battery warning level threshold
      description: Battery sensors below threshold are assumed to be low-battery.
      default: 20
      selector:
        number:
          min: 5.0
          max: 100.0
          unit_of_measurement: '%'
          mode: slider
          step: 5.0
    time:
      name: Time to test on
      description: Test is run at configured time
      default: '10:00:00'
      selector:
        time: {}
    day:
      name: Weekday to test on
      description: 'Test is run at configured time either everyday (0) or on a given
        weekday (1: Monday ... 7: Sunday)'
      default: 6
      selector:
        number:
          min: 0.0
          max: 7.0
          mode: slider
          step: 1.0
    notify_device:
      name: Device to notify
      description: Device needs to run the official Home Assistant app to receive notifications
      selector:
        device:
          integration: mobile_app
variables:
  day: !input 'day'
  threshold: !input 'threshold'
  counttotal: "{{ states.sensor \
| selectattr('attributes.device_class','eq','battery') \
| sort(attribute='state') | rejectattr('state', 'in', ['0', '100']) \
| list | count }}"
  countlow: "{{ states.sensor \
| selectattr('attributes.device_class','eq','battery') \
| sort(attribute='state') | rejectattr('state', 'in', ['0', '100']) \
| selectattr('state', 'lessthan', threshold|string) | list | count }}"
  listtextlow: "{% for batt in states.sensor \
| selectattr('attributes.device_class','eq','battery') \
| sort(attribute='state') \
| rejectattr('state', 'in', ['0', '100']) \
| selectattr('state', 'lessthan', threshold|string) \
| list -%}
{{ batt.attributes.entity_id }}
{{ batt.attributes.friendly_name }} is {{ batt.state }}% 

{% endfor %}"
  notification_message: "{% if countlow > 0 -%}{{countlow}} out of \
{{ counttotal }} device batteries are low:

{{listtextlow}}
{%- else -%}
All {{counttotal}} device batteries are ok!
{% endif %}"
trigger:
- platform: time
  at: !input 'time'
condition:
- condition: template
  value_template: '{{ sensors != '''' and (day | int == 0 or day | int == now().isoweekday())
    }}'
action:
- device_id: !input 'notify_device'
  domain: mobile_app
  type: notify
  title: 'Battery Check'
  message: '{{ notification_message }}'
- service: persistent_notification.create
  data:
    title: 'Battery Check'
    message: '{{ notification_message }}'
    notification_id: battery-check

Hi @davet2001, thanks for this modified blueprint. It helps. There is some small bugs when we select threshold at level5% and 100%. when select 5%, system see it as 50% and report battery that is <50%, when select 100%, system report all battery OK. Could you help to see if this can be fixed? Thanks for your help.

not sure if this is still active, but when I'm running the blue print, I get all my sensors reporting, not mater what threshold I select, and no mater what the batteries levels are
select 20% threshold, lists every dive, some with 23% battery, some with 99% battery

For anyone else just finding this, I don't think it works any more. Devices all report as being fine even if they fall below the threshold you set.